It is often necessary to add a branch line to a piping network carrying fluid. If the network is pressurized and working, it may not be practical to shut the system down and drain the fluid so that a pipe element in the network may be cut and a “tee” fitting added to connect the branch line to the existing network. Equally onerous is the addition of a saddle connection, which requires that a hole be drilled in the pipe element to effect a connection. This is especially true for large systems, such as fire suppression sprinkler systems in buildings, where it is both impractical and unsafe to take the sprinkler system offline and drain it so that additional branches may be added to an existing network. For certain applications, such as hospital water service, it is universally acknowledged as unacceptable to interrupt water service for such routine alterations.
This problem has been long recognized and a method of “hot tapping” was developed which allows a branch line to be added to a pressurized piping network without depressurizing and draining the system.
Because hot tapping requires that an opening be cut in a pipe element of the existing piping network, prior art hot tapping methods and devices suffer the disadvantage of swarf, coupons and other debris from the cutting process becoming entrained in the fluid within the piping network. The debris can create serious problems as it may damage pumps and turbines in the system, jam valve actions or clog venturi and orifices. Of particular concern is the potential for debris to clog sprinkler heads of fire suppression systems. It would be advantageous to have a device and a method for hot tapping which does not suffer such disadvantages.